Ingress/Egress Call Module

ABSTRACT

A system monitors calls for a service provider. A number of simultaneous communications of a given technology type is monitored for either inbound communications and/or outbound communications associated with at least one service provider. A determination is made if the number of simultaneous communications from the service provider is in excess of a adjustable but set number of simultaneous communications of a given technology type that are permissible. A predetermined action is taken if the number of simultaneous calls or text messages (e.g., SMS, IM, email) is in excess of the set limit, e.g., the call may be terminated or other action taken. Both voice communications and/or non-voice communications (such as SMS, IM, Email, or MMS) can be monitored and throttled.

This application claims priority from U.S. Provisional Application61/071,547 entitled “INGRESS/EGRESS CALL MODULE”, filed May 5, 2008, andU.S. Provisional Application 61/129,006 entitled “INGRESS/EGRESS CALLMODULE”, filed May 30, 2008, the entireties of which are expresslyincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to communications. More particularly,it relates to throttling on ingress to and egress from a central systemfor voice or text-based communications.

2. Background of the Related Art

9-1-1 is a phone number widely recognized in North America as anemergency phone number that is used to contact emergency dispatchpersonnel. Enhanced 9-1-1 (E9-1-1) is defined by an emergency call beingselectively routed to an appropriate PSAP, based on a special identifier(a TN or “telephone number” that is either an ANI or “Automatic NumberIdentification” that identifies the caller's phone or the TN is a P-ANI,or “Pseudo Automatic Number Identifier”, also referred to as “ESxK”,that only identifies the PSAP the call should route to and the companyrouting the call), and includes the transmission of callback number andlocation information when 9-1-1 is used. E9-1-1 may be implemented forlandline, cellular or VoIP networks. A Public Safety Answering Point(PSAP) is a dispatch office that receives 9-1-1 calls from the public. APSAP may be a local, fire or police department, an ambulance service ora regional office covering all services. As used herein, the term “PSAP”refers to either a public safety answering point (PSAP), or to anEmergency Call Center (ECC), a VoIP term.

Regardless of the network type, a 9-1-1 service becomes E-9-1-1 whenautomatic number identification and automatic location informationrelated to the call is provided to the 9-1-1 operator at the PSAP.

The current 911 infrastructure is designed to route a live voice call toa local public safety answering point (PSAP). This requires that voicecircuits be available. The result of an E911 call is a direct circuitswitched voice connection between an emergency service requestor and asuitable responder. 911 is further enhanced with the ability to deliverlocation over a data channel in parallel to the call. The location datais typically staged in a database that is queried by the PSAP todetermine location information.

FIG. 6 shows a conventional landline public safety access point (PSAP)to automatic location identifier (ALI) connection.

In particular, FIG. 7 shows a PSAP 400 connected to one AutomaticLocation Identifier (ALI) database 401. Upon receiving a 9-1-1 call, thePSAP 400 queries the ALI 401 for location data. The ALI database 401accepts the query from the PSAP 400 for location. The query includes thetelephone number of an emergency caller. The ALI database 401 relatesthe received telephone number to a physical street address and providesthat street address (location information) back to the PSAP 400 in amanner that works for the customer premise equipment (CPE) display atthe PSAP 400.

An ALI is typically owned by a local exchange carrier (LEC) or a PSAP,and may be regional (i.e. connected to many PSAPs) or standalone (i.e.connected to only one PSAP).

FIG. 7 shows a context diagram for a conventional non-landlinepositioning center (e.g., an Internet based Voice over Internet Protocol(VoIP) positioning center).

In particular, the ALI database 401 includes a conventional emergencyservices key (ESQK or ESRK) in a location request sent to an appropriatepositioning center 402 (XPC). The emergency services key (ESQK or ESRK)is used by the positioning center 402 as a key to look up the locationand other call information associated with the emergency call.

In non-landline telephony, the PSAPs 400 query the ALI 401 for locationinformation. However, the ALI 401 is not pre-provisioned with locationdata for non-landline calls (e.g. cellular, VoIP etc) and mustcommunicate with other network entities to obtain and deliver locationdata to the PSAP 400.

911 calls require voice circuits to be available to complete the voicecall to a PSAP. For the most part, PSAPs are capable of receiving onlyvoice calls. Connectivity with a PSAP, established either through theexisting time division multiplexed (TDM)-based emergency servicesnetwork (ESN), or directly over the public switched telephone network(PSTN) to the PSAP, is managed through dedicated telephone switches thatcannot be directly dialed.

The present inventors have appreciated that during times of regionalcrises, such as during a hurricane, the local wireless infrastructurecan become overloaded by call volume. This was experienced during theSep. 11, 2001, terrorist attacks during which voice telecommunicationsalong the east coast was subjected to service failures.

Existing technology uses a limit on the number of voice circuits ornetwork bandwidth available for voice calls or other calls based onother technologies. Existing technology is not dynamic and cannot becontrolled from a central access point to a system. Moreover, existingtechnology cannot deliver location information at the time of call setup and cannot take advantage of the diversity, redundancy, andresiliency of IP networks.

SUMMARY OF THE INVENTION

In accordance with the principles of the present invention, a method ofmonitoring a state for calls for a service provider comprisesmonitoring, from a central call routing system, a number ofcommunications for at least one of inbound communications and outboundcommunications associated with at least one service provider. Adetermination is made from a state machine if the number ofcommunications from the at least one service provider is in excess of apredetermined number of communications that are permissible. The statemachine performs a predetermined action if the number of callsassociated with the at least one service provider is in excess of thepredetermined number of communications.

In accordance with another aspect of the invention, a system forthrottling calls and data messaging being handled by a given serviceprovider comprises a central call routing system to monitor a number ofsimultaneous communications of a given technology type associated with agiven service provider. A state machine dynamically determines a numberof simultaneous communications associated with the given serviceprovider, and initiates a predetermined action against any simultaneouscommunication in excess of a predetermined limited number ofsimultaneous communications.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the present invention will become apparent tothose skilled in the art from the following description with referenceto the drawings, in which:

FIGS. 1 depicts exemplary message flows for an exemplary communicationssystem, in accordance with the principles of the present invention.

FIGS. 2 depicts exemplary message flows for another exemplarycommunications system, in accordance with the principles of the presentinvention.

FIG. 3 shows an exemplary ingress/egress system and message flow foranother exemplary communications system, in accordance with theprinciples of the present invention.

FIG. 4 shows exemplary message flow for yet another exemplarycommunications system, in accordance with the principles of the presentinvention.

FIG. 5 shows an exemplary message flow for another exemplarycommunications system, in accordance with the principles of the presentinvention.

FIG. 6 shows a conventional landline public safety access point (PSAP)to automatic location identifier (ALI) connection.

FIG. 7 shows a context diagram for a conventional non-landlinepositioning center (e.g., an Internet based voice over Internet Protocol(VoIP) positioning center).

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The present invention prevents any one voice service provider or onecommunication technology from monopolizing a central system's resources.

In accordance with the principles disclosed herein, a module keeps statefor all voice calls or non-voice-based requests (SMS, IM, Email) inboundto a central system and outbound from a central system. Any requestattempt (ingress) from a service provider in excess of their voice, SMS,IM, or Email allowance are immediately terminated or some other defaultor chosen action. Additionally or alternately, any request, regardlessof originating service provider, in excess of a set limit for a givencommunication technology (e.g. only 5 concurrent SMS requests areallowed to the central system), are immediately terminated or some otherdefault or chosen action.

Similarly or alternatively, preferably any request that would result inan excess of the allowed number of attempted completions (egress)regardless of service provider or technology is immediately terminatedor some other default or chosen action.

The present invention provides benefits to multiple voice serviceproviders (VSP) such that they can use the same circuit(s) as long asthe monitoring device and/or IECSM can determine which VSPs calls arewhich. Moreover, local number portability is no longer an issue becausethe IECSM can inform systems downstream which carrier is using aspecific TN for the current active call.

The invention allows multiple VSPs to use the same circuits or trunks.Moreover, it provides a solution that does not require the locking andunlocking of ported telephone numbers (LNP).

The present invention has applicability with virtually any voice serviceprovider that operates a central call routing system. In accordance withthe invention, the central call routing system throttles calls, SMSs,emails, IMs, etc. based on both incoming calls and data messages fromother VSPs as well as outgoing calls and data messages to theagency/service that the relevant central call routing system serves.

The present invention provides a Next Generation 9-1-1 messaging centerthat allows a selective router to receive TDM calls and make routingdecision for those calls. The Next Generation 9-1-1 messaging centerdisclosed herein comprises a media gateway, a back-to-back user agent(B2BUA) that allows SIP body rewrites, and software that integrates withthe B2BUS and allows it to query various databases.

The Next Generation 9-1-1 messaging center disclosed herein converts atime division multiplex (TDM) call to voice over Internet protocol(VoIP), and inserts the appropriate location information into the SIPInvite body in the form of PIDF-LO as recommended by NENA i3 standards.The Next Generation 9-1-1 messaging center brings voice, video, and textfrom any originating device to Internet Protocol (IP) capable PSAPs.

The Next Generation 9-1-1 messaging center also intercepts selectivetransfer requests from Internet Protocol (IP) public service accesspoints (PSAPs) and determines if the responder to receive that transferis IP capable or TDM capable. If the responder is IP capable, the NextGeneration 9-1-1 Messaging Center forwards the call over the IP network.If the responder is TDM capable, the Next Generation 9-1-1 messagingcenter determines the dialing pattern necessary for the selective routerand sends calls to the selective router for completion.

The Next Generation 9-1-1 infrastructure disclosed herein replaces oraugments selective routers and automatic location identification (ALI)databases. The Next Generation 9-1-1 systems disclosed herein eliminatethe need for MPCs, GMLCs, and VPCs. ALI databases continue to providetraditional data for Local Exchange Carrier (LEC) subscribers. Othercustomer operated databases may be expanded to provide further personalinformation.

The invention provides a module that keeps state information for allvoice calls inbound to a system and outbound from a system. Any call setup attempt (ingress) from a voice service provider in excess of therelevant allowance is immediately terminated (or other default of chosenaction). Similarly, any call attempt that would otherwise result in anexcess of the allowed number of attempted completions (egress) wouldinstead be immediately terminated (or other default or chosen action).

Those having particular use of the invention include any voice serviceprovider that operates a central call routing system. The inventionprovides the ability to throttle calls or data messages based on bothincoming calls from other VSPs as well as outgoing calls to theagency/service that the relevant central call routing system serves.

FIG. 1 shows exemplary message flow for an exemplary communicationssystem, in accordance with the principles of the present invention.

In particular, as shown in FIG. 1, various communications areillustrated between an “Ingress/Egress Call State Machine” (IECSM) 114,a central call routing system 112, a voice service provider 110, a mediagateway 115, a selective router or other central call routing system(hereafter referred to as a selective router 118), and a PSAP or otheragency receiving calls from a central call routing system (hereafterreferred to as a receiving agency 120).

In step 1 of FIG. 1, a voice service provider (VSP) 110 initiates a callto the central call routing system 112.

In step 2, monitoring devices (not shown) within the central callrouting system 112 detect all calls and report the state to an IECSM114.

In step 3, an IECSM 114 receives notification of a call attempt from themonitoring devices within the central call routing system 112. Forexample, if a VSP 110 is allowed, e.g., no more than three simultaneouscalls, and the call in question would be the fourth call, the IESCM 114sends notice to the monitoring device within the central call routingsystem 112 to perform some desired action, such as to immediatelyterminate the fourth call. Similarly, for example, if a set limit isthat only ten calls are allowed to simultaneously egress the centralcall routing system 112, and ten calls are already currently active,then on the next (i.e., 11^(th)) call attempt from a VSP 110, the IECSM114 performs some desired action on the call, such as termination, evenif the call would be the VSPs 110 only active call.

The IECSM 114 is preferably capable of informing other systems regardingwhich VSP 110 is using a given telephone number (TN), thus changing mostprocesses involving Local Number Portability.

In step 4, a call attempt is passed to a central call routing system112.

In step 4 a, if the central call routing system 112 is IP-based, the TDMcalls must be converted to IP. On the other hand, as depicted in step 4b, if the central call routing system 112 is TDM based, the VoIP callsmust be converted to TDM.

In step 5, a receiving agency 120 receives the call.

In step 6 a, the VSP 110 terminates the call, or as depicted in step 6b, a receiving agency 120 terminates the call. In either scenario, theIECSM 114 changes the “ingress” state for that VSP 110 as well aschanges the “egress” state for the agency 120 receiving calls.

FIG. 2 shows exemplary message flow for another exemplary communicationssystem, in accordance with the principles of the present invention.

In particular, as shown in FIG. 2, various communications areillustrated between a voice service provider 110, a media gateway (Note:In this and other uses, the term media gateway should be consideredsynonymous with the media gateway and the media gateway controller thatmay be used in conjunction with it.) 115, a selective router or othercentral call routing system (hereafter referred to as a selective router118), and a PSAP or other agency receiving calls from a central callrouting system (hereafter referred to as a receiving agency 120), anInternet Protocol (IP) PSAP 122, a police responder 130, a NextGeneration Messaging Center (NGMC) 124, a Location Information Server(LIS) 126, and a Automatic Location Identification (ALI) Database 128.

The LIS 126 can be a database service that provides locations ofendpoints. In practice, “LIS Steering” may be required to determinewhich of a possible plurality of LISs to query.

As shown in step 1 of FIG. 2, a Voice Service Provider 110 sends a callout on a 9-1-1 trunk (not shown).

In step 2, the call reaches the selective router 118 and is routed usinga telephone number to a trunk group.

In step 2 a, a trunk group terminates at a media gateway 115 because thePSAP is now an IP PSAP 122.

In step 2 b, a trunk terminates at a TDM based PSAP 120.

In step 3, the media gateway 115 messages the NGMC 124.

In step 4, the NGMC 124 queries either an LIS 126 or ALI 128 (which oneis optional but one must be used) using a telephone number to retrievethe location information.

In step 5, the NGMC 124 sends a new message with Presence InformationData Format-Location Object (PIDF-LO) to the media gateway 115. In step6, the IP PSAP 122 receives location information at the time of call setup.

In step 6 a, the call goes to an IP based PSAP, e.g., IP PSAP 122, basedon a trunk decision made by the selective router 118.

In step 6 b, the call goes to a TDM based PSAP, e.g., TDM PSAP 120,based on a trunk decision made by the selective router 118.

In step 7, the IP PSAP 122 may initiate a selective transfer using, inthis case, a SIP Invite to SOS.Police.

In step 8, the media gateway 115 again queries the NGMC 124.

In step 9, the NGMC 124 determines who the responder is and thendetermines how to reach that responder using a database of responders:e.g., using either another Session Initiation Protocol (SIP) UniformResource Identifier (URI), or using a dialing pattern that the selectiverouter can interpret, such as “1”.

In step 10, the NGMC 124 sends what it has determined to the mediagateway 115.

In step 11, the media gateway 115 either sends the SIP universalresource indicator (URI) to another IP node, or, as in the example inFIG. 2, will send the dialing pattern to the selective router 118.

In step 12, the selective router 118 interprets the dialing pattern andsends the call out to the trunk group of the appropriate police or otheremergency responder 130.

FIG. 3 shows an exemplary ingress/egress system and message flow foranother exemplary communications system, in accordance with theprinciples of the present invention.

In particular, as shown in FIG. 3, call flow is illustrated between anIECSM 114, a central call routing system 112, a Communications ServiceProvider (CSP) 111, a media gateway 115, a selective router or othercentral call routing system (hereafter referred to as a selective router118), and a PSAP or other agency receiving calls from a central callrouting system (hereafter referred to as a receiving agency 120).

In step 1 of FIG. 3, a CSP 111 initiates a request to the central callrouting system 112. It is noted that in the example shown, it is assumedthat Short Message Service (SMS), Instant Messaging (IM), Emailrequests, etc. will use another system to initiate an IP call request.This request may look to the receiving system like another VoIP callrequest.

In step 2, monitoring devices within the central call routing system 112detect all requests and report the state to the IECSM 114.

In step 3, an IECSM 114 receives notification of a request from themonitoring devices (not shown) within the central call routing system112. For example, if a CSP 111 is subject to a set limit of no more thanthree simultaneous requests, and a given request in question would bethe fourth simultaneous request, the IECSM 114 sends notice to themonitoring device within the central call routing system 112 to performsome desired action, such as terminate the call.

Similarly, as another example, if only ten simultaneous requests areallowed to egress the central call routing system 112, and ten requestsare currently active, then on the next request from a CSP 111, the IECSM114 performs some desired action on the call, such as termination, evenif the call would be the CSP's 111 only active call.

Additionally, the IECSM 114 can be configured to allow only a givennumber of requests (e.g., three) originated from a particular technology(e.g., from an SMS system). In this case, upon receipt of a 4^(th)request made over SMS, the IECSM 114 performs some desired action on therequest, such as termination.

The IECSM 114 can also inform other systems regarding which CSP 111 isusing a given telephone number, thus changing most processes involvingLocal Number Portability.

In step 4, the request is passed to a central call routing system 112.In step 4 a, if the central call routing system 112 is IP-based, the TDMcalls must be converted to IP.

In step 4 b, if the central call routing system is TDM based, the VoIPcalls must be converted to TDM. In the case where the request is not acall (such as SMS, IM, or Email), the request is passed forward byanother system as if it were a VoIP call so that services can beprovided by the central call routing system 112.

In step 5, an end agency, e.g., PSAP 120, receives the request andperforms the appropriate action, i.e., either carries out a voiceconversation or provides information to communicate to an SMS, IM, orEmail user.

In step 6 a, a CSP 111 terminates the call, or as depicted in step 6 b,the receiving agency, e.g., PSAP 120, terminates the call. In eitherscenario, the IECSM 114 changes the “ingress” state for that CSP 111,i.e., changes the “ingress” state for the technology in question, aswell as changes the “egress” state for the agency receiving calls.

FIG. 4 shows an exemplary message flow for another exemplarycommunications system, in accordance with the principles of the presentinvention.

In particular, as shown in FIG. 4, various communications areillustrated between a Voice Service Provider 110, a selective router orother central call routing system (hereafter referred to as a firstselective router 118 a and a second selective router 118 b), a firstselective router 118 a, a PSAP or other agency receiving calls from acentral call routing system (hereafter referred to as a first receivingagency 120 a and a second receiving agency 120 b), a first PSAP 132, anational media gateway network 134, a National Transfer VPC 136, a firstALI 128 a, and a second ALI 128 b.

In step 1 of FIG. 4, the Voice Service Provider 110 sends a call intothe local E9-1-1 system.

In step 2, the first selective router 118 a sends the call to the firstPSAP 120 a.

In step 3, the first PSAP 120 a determines that the call must betransferred to a PSAP not connected to their selective router, e.g., thesecond PSAP 120 b. The first PSAP 120 a dials a 10-digit number thatcorresponds to an IVR system (not shown) in the National Transfer VPC136. The IVR system retrieves the call back number and the destinationPSAP, e.g., second PSAP 120 b, or destination city/state.

In step 4, the National Transfer VPC 136 retrieves location informationfrom the local ALI, e.g., ALI 128 a, querying as if it is a PSAP. TheNational Transfer VPC 136 assigns the call an ESRN and ESQK appropriateto the location provided to the IVR.

In step 5, the call is sent out on the national media gateway network134.

In step 6, the national media gateway network 134 forwards the call tothe second selective router 118 b.

In step 7, the second selective router 118 b forwards the call to thesecond PSAP 120 b provided to the National Transfer VPC's 136 IVR.

In step 8, the second PSAP 120 b queries the local ALI 128 b for anESQK.

In step 9, the national transfer VPC 136 provides the caller's callbacknumber and location information.

In step 10, the local ALI 128 b delivers the caller's information.

FIG. 5 shows an exemplary message flow for another exemplarycommunications system, in accordance with the principles of the presentinvention.

In particular, as shown in FIG. 5, various communications areillustrated between a first service provider 110 a, a second voiceservice provider 110 b, a third voice service provider 110 c, an IPselective router 140, a first media gateway 115 a, a second mediagateway 115 b, a selective router 118, and a PSAP or other agencyreceiving calls from a central call routing system (hereafter referredto as a receiving agency 120). The IP selective router 140 includes aPolicy Routing Function (PRF) 142, a VPC/Emergency Services RoutingProxy (ESRP) 144, and a conference bridge 146.

The ESRP 144 preferably is a SIP proxy server that selects the next hoprouting within an ESInet based on location and policy. A “PSAP Proxy” isused in some implementations to facilitate completion of calls to LegacyPSAPs.

The Policy Routing Function (PRF) 142 is preferably an entity thatdefines attributes such as hours of operation, default routing, andoverflow routing.

In step 1 a of FIG. 5, all VoIP Service Providers 110 a, 110 b, and 110c, send calls to the IP Selective Router 140 within the system 150 thatprovides parallel service to a TDM-based selective router 118.

In step 2 b, the IP Selective Router 140 routes a call to a mediagateway 115 b local to the correct receiving agency 120.

In step 3, the media gateway 115 b converts a call back to TDM andpasses the call to the receiving agency's 120 TDM-based PBX over localcables, just as if they were trunks from a selective router 118.

The IP Selective Router 140 interprets the receiving agency's 120equipment signaling for a selective transfer and sets up the call to theresponder from the receiving agency's 120 local media gateway 115 busing a PRI.

In step 1 b, the voice service provider 110 b sends calls to the mediagateway 115 b local to the TDM based selective router 118.

In step 2 a, the media gateway 115 a local to the TDM based selectiverouter 118 signals to the IP selective router 140.

In step 3, the IP selective router 140 routes the call, through themedia gateway 115 a local to the TDM selective router 118, and to amedia gateway 115 local to the correct receiving agency 120.

In step 4, the media gateway 115 b local to the receiving agency 120converts the call back to TDM and passes the call to the receivingagency's 120 TDM PBX over local cables, just as if they were trunks froma selective router 118.

The IP selective router 140 interprets the receiving agency 120equipment signaling for a selective transfer and sets up the call to theresponder from the receiving agency's 120 local media gateway 115 busing a PRI.

One of ordinary skill in the art will appreciate that the presentinvention can be used with an Emergency Call Routing Function (ECRF)that receives location information (either civic address orgeo-coordinates) as input.

The ECRF uses the information to provide a URI that routes an emergencycall toward the appropriate PSAP for the caller's location.

One of ordinary skill in the art will appreciate that the presentinvention can also be used with a Location Validation Function (LVF)that validates location objects against the next generation addressdata.

Advantageously, the invention may be implemented without the need forimmediate PSAP upgrades. It enables transfers from any selective routersdisclosed herein to any other selective router disclosed herein withonly minor configuration changes. No interoperability issues arepresented or additional software loads required.

Implementation of the IP selective router disclosed herein provides fora slow migration to IP call routing while at the same time extends thelife of existing selective routers. The invention allows for dynamicaddition of call answering stations at a PSAP by simple activation ofadditional DSOs from the local media gateway into a PBX. It establishesa diverse, redundant IP network for use by voice service providers toPSAPs. Additional services will also be able to make use of the networksdisclosed herein.

The Next Generation Messaging Center disclosed herein makes selectiverouters and ALI databases next generation capable. The Next GenerationMessaging Center disclosed herein establishes a diverse, redundant IPnetwork for use by voice service providers to PSAPs. Additional servicesare able to utilize this network. The invention affects only PSAPsmigrating to IP, with no disruption to other E9-1-1 customers.

While the invention has been described with reference to the exemplaryembodiments thereof, those skilled in the art will be able to makevarious modifications to the described embodiments of the inventionwithout departing from the true spirit and scope of the invention.

1. A system for throttling calls and data messaging being handled by agiven service provider, comprising: a central call routing system tomonitor a number of communications of a given technology type associatedwith a given service provider; and a state machine to dynamicallydetermine a number of simultaneous communications associated with saidgiven service provider, and to initiate a predetermined action againstany simultaneous communication in excess of a predetermined limitednumber of simultaneous communications. 2-15. (canceled)